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343,239 | 2 apache OSX Servers behind the router with 1 Public IP address using Reverse Proxy solution | So Confused myself, so I need an expert reverse proxy help here please. Server 1 on Public IP - 173.xxx.xxx.xxx port 80 (LAN IP is 10.1.10.2). Server 1 also has a local DNS enabler so that local users are able to browse all of our 4 registered domains within our local LAN. Server 2 is on local LAN with local IP 10.1.10... | ProxyPass configuration would be part of Server 1's configuration. This is the host acting as the proxy for Server 2. You don't need to make any change to Server 2. You should be able to continue using vhosts. I got frustrated though and just setup my proxy with [CODE] statements. It works well for what I needed. I thi... | 0 | 2 | 610 | 2011-12-21T19:29:26.980 | infrastructure | serverfault.com | |
165,008 | Can I get a C++ Compiler to instantiate objects at compile time | I am writing some code that has a very large number of reasonably simple objects and I would like them the be created at compile time. I would think that a compiler would be able to do this, but I have not been able to figure out how. In C I could do the the following: [CODE] Using #C++* each object has it constructor ... | In C++11 you can use a [CODE] constructor like this: [CODE] GCC 4.7.1 in C++0x mode supports constexpr constructors at compile time, and the above code works as desired, with no calls to the Info constructor in the generated code. Note that the compiler is not required to do full construction at compile time - in princ... | 7 | 6 | 8,016 | 2012-09-15T22:10:40.290 | api_errors | softwareengineering.stackexchange.com | |
435,642 | Shared files folder in Amazon Elastic Beanstalk environment | I'm working on a Drupal application, which is planned to be hosted in Amazon Elastic Beanstalk environment. Basically, Elastic Beanstalk enables the application to scale automatically by starting additional web server instances based on predefined rules. The shared database is running on an Amazon RDS instance, which a... | Have you considered using [CODE] via [CODE] with your shared files stored in S3? http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/customize-containers-ec2.html I have used [CODE] to deploy shared files (sitemaps) that are built by our app server (and stored in S3). [CODE] | 4 | 0 | 2,421 | 2012-10-07T09:34:00.163 | pipeline_ops | serverfault.com | |
506,591 | fix kernel on Xen Server hypervisor vps | I have a cloud server hosted at Rackspace, and they use Xen Server hypervisor. I was running Ubuntu 12.04, and really messed up by attempting to do a release upgrade manually. The hypervisor apparently doesn't get along with the changes made to GRUB (I think; there could be more) and thus does not reboot; it gets stuck... | So the problem wasn't particularly correctly analyzed by anyone here, but the higher-tier Linux Admins at Rackspace were instrumental in solving this problem. I replaced my GRUB2 conf with what Alien Life Form gave me, but changed the root line to: [CODE] Then, in my [CODE] , I removed the [CODE] line, so that it could... | 2 | 0 | 1,321 | 2013-05-10T06:20:54.363 | infrastructure | serverfault.com | |
152,158 | Conditional Database View of Postgresql | I have a situation here. Currently I have two polling tables (poll_one and poll_two) which will poll data from outside data-source. This two tables will keep interchange between each other. one checking table (check_poll) which tells me which tables (poll_one or poll_two) is active one user edit table (edit) which stor... | It's not exactly clear how the [CODE] or the [CODE] table is to be chosen but something like this should work (I assume that the [CODE] table has a single row always): [CODE] or even combine the two subqueries in one: [CODE] | 0 | 2 | 512 | 2016-10-13T06:40:04.467 | database_errors | dba.stackexchange.com | |
752,946 | VPS Upload speeds < 1 mbps | I have a Centos server running in eastern canada. When I use speedtest.net and connect to a server up there, I get around 30 down. If I use speedtest-cli and connect to a server down here I get about 40 up. However, when I download directly from my server, I get around 100kbps. Webdav crashes because its so slow. ethto... | Webdav is almost always very slow. Try transfering some files by regular http, ftp and/or scp and see if that is faster. If it is, its a software issue with whatever you use for webdav. Its also possible the network between you and speedtest.net is great, and between the server and speedtest.net is great, but the netwo... | 0 | 1 | 1,280 | 2016-01-31T02:18:32.073 | infrastructure | serverfault.com | |
360,174 | Patterns for validating complex condition trees? | I have to write API validation functions where the rules can get hairy and have many outputs depending on the branch taken. These validation functions end up being a nesting of lots of IF conditions here and there (I try to stick to simple condition IF for simplicity), where I have lots of comments to help what's happe... | Write simple boolean functions and combine them. [CODE] Use Early Exit [CODE] Use default values to avoid null checks [CODE] Rewrite the logic so it requires less conditions. Use a validation library Write a Rules Engine ..etc | 3 | 1 | 133 | 2017-11-03T01:26:44.620 | data_quality | softwareengineering.stackexchange.com | |
1,080,735 | Docker+Synapse+Traefik v2 stops working when I make a separate backend network | I'm trying to set up a Matrix Synapse server using Docker and a Traefik v2 reverse proxy. My setup works if I define a single network in my docker-compose file and have Traefik, Synapse and postgres all use that network. However, based on what I've learnt about Docker so far, I should put postgres on a separate network... | Traefik doesn't know which IP of the container it should try to connect. You're close with [CODE] but that's not really the name of the network. The network will get a prefix for the project or stack name. To hard code the network name, you can use the name field in the final network section (this is specific to versio... | 1 | 2 | 742 | 2021-10-16T10:10:16.543 | warehouse_errors | serverfault.com | |
942,954 | Can't Start HTTPD After Update | I'm unable to start my previously working [CODE] (2.4.6) after updating my instance(CentOS 7). I first checked the status via [CODE] , which yielded: [CODE] Not really helpful, there isn't a specific error message to point me somewhere. Therefore I did a [CODE] which showed a problem with a Let's Encrypt certificate fi... | I finally figured it out. It seems there was a problem with my error/request logs I used for my available sites. It wasn't properly guiding me there through Apache's own status messages(in reality, Apache was a bit cryptic through [CODE] or [CODE] ) but with the comments above, I was able to track it down there and onc... | 0 | 0 | 1,340 | 2018-12-05T08:20:24.593 | infrastructure | serverfault.com | |
1,015,458 | Why does Load Average of my Linux hosting server keeps swinging from 6 to 33? | Lately, I've noticed a weird behaviour on my production server of a moderately high traffic WordPress website. (concurrent realtime traffic around ~1500) The server is capable: [CODE] The issue is that the Load Average (LA) stays at 6 for approx 30 mins, then rises steadily to around 33 and then stays at 33 for approx ... | Per your screenshot showing 599% CPU in [CODE] , the database is the source of your problems. I would put all the files you 'tweaked' back to their default settings. Chances are you changed stuff after random googling when you didn't know what the actual problem was. After that, you should run MySQL Tuner to get sugges... | 0 | 1 | 110 | 2020-05-03T15:45:43.577 | api_errors | serverfault.com | |
315,387 | A Way To Determine IP Range From CIDR? | Possible Duplicate: How does Subnetting Work? Is there a formula or a calculator for determining an IP address from CIDR that I was given: 38.103.17.160/27? I would like to know the entire range of IP addresses from what I was given, but I have no idea how to break it down. I am far, far from being a networking person ... | Yes. That little number is supposed to give you that very information, but does require a bit of calculating. Have a look at this article which explains subnetting and how to calculate how many hosts/subnets that /27 refers to: How does IPv4 Subnetting Work? And once you know how it works, you can use some calculators ... | 1 | 0 | 5,956 | 2011-09-26T00:08:45.600 | data_quality | serverfault.com | |
222,971 | Missing wsrep variables in mysql / percona / galera cluster | I set up a small mysql/percona/galera cluster using the percona cluster docker image, with 3 nodes. I followed the documentation written here After starting up the whole cluster, I'm missing some of the wsrep variables. For instance wsrep_local_state_comment . (among many others) Does anyone knows why is this happening... | After starting up the whole cluster, I'm missing some of the wsrep variables. I'm not sure if this is the issue, but [CODE] is not a wsrep variable, it's a status variable. Which means you have to use [CODE] rather than [CODE] , i.e. in this case: [CODE] And more generally: [CODE] | 0 | 1 | 142 | 2018-11-20T13:05:23.490 | database_errors | dba.stackexchange.com | |
546,253 | I accidently zipped my whole server | Alright if anyone wants to play god and work miracles i'm down. So, i was given the task of making a script that found files that are older than 6 months, zipped them and then deleted them. On my way in making tihs script i ran this : [CODE] And that gave EVERY SINGLE FILE a .gz extension. Now i undid it as soon as i n... | This will depend on whether the filesystems are repaired enough for you to be able to mount those partitions from a LiveCD. Don't bother trying to boot the system yet. First, mount the partitions and unzip all the .gz files. This will give you working copies of init and system binaries. Then you can use grub to repair ... | 10 | 8 | 1,145 | 2013-10-15T19:52:27.903 | infrastructure | serverfault.com | |
192,703 | WHERE 1 = 2 returns a row | Any idea, why the first of the following queries returns a row with -1, NULL, although it has a [CODE] ? Only when I put the query in another subquery it works correct (and returns an empty result set). Tested on Microsoft SQL Server 2014 and 2016 [CODE] | An aggregate query without a [CODE] is a scalar aggregate and (in the absence of any [CODE] clause) returns exactly one row. So if you do [CODE] Or [CODE] Both would return the value [CODE] rather than an empty result set. If you add a [CODE] it then becomes a vector aggregate and returns one row per group (So would re... | 3 | 6 | 192 | 2017-12-08T14:20:27.063 | database_errors | dba.stackexchange.com | |
41,622 | Not able to run application through emulator in mac | Code: [CODE] Getting this type of error in console: [CODE] | As per my experience in the qa services, it appears like required ADB paths are not completely configured on the Mac machine. So for that, along with the ANDROID_HOME variable, 02 additional paths: pointing to the 'platform-tools' and 'platforms' folder, inside the Android SDK folder also needs to be initialized in the... | 0 | 0 | 602 | 2019-11-22T05:37:30.747 | data_quality | sqa.stackexchange.com | |
26,774 | Optimizing random function | If I wanted to determine the parameters of a deterministic algorithm that optimise some performance measure, there are any number of well-known techniques I could try. My problem concerns an algorithm whose behaviour is stochastic. Mathematically, the aim is to maximise $\mathbb{E}f(\mathbf{x})$, where for any $\mathbf... | Bayesian Optimization can be useful to find the optimal value for black-box functions without assuming a functional form. | 4 | 2 | 196 | 2018-01-18T09:35:56.097 | data_quality | datascience.stackexchange.com | |
316,514 | Windows Firewall has port 80 open but prevents Apache from making connections | I have a Windows 7 machine serving a very few (but important!) pages. I have an exception that allows any traffic to port 80*, but Apache 2.2 still can't serve pages (though I can see them from the machine itself). If I disable the Windows Firewall entirely, though, I can ping the box and load pages. What else do I nee... | Whether or not port 80 is open on your firewall, doesn't mean that ping will start working if Apache is running correctly. Ping uses ICMP which is a protocol of it's own that needs to be opened on the firewall in order to receive ping replies from your machine. So don't count on ping to verify if your apache configurat... | 12 | 12 | 52,385 | 2011-09-28T19:03:37.727 | infrastructure | serverfault.com | |
316,907 | Invoke-AzVMRunCommand on Azure VM using domain user | I am working on ARM template to setup SQL server VM on Azure with Always on High availibility setup using Win server 2019 and SQL Server 2019 Enterprise image. I am trying to automate everything using ARM template. Now, I need to execute SETSPN commnad on one of the Azure SQL Server VM using AMR template for which I us... | I'm not sure why using setspn as System isn't a valid thing for you to do, but if you want to use a domain user you'll need to store creds in the automation account and setup a hybrid runbook worker. It's kind of a pain. | 0 | 0 | 648 | 2022-09-13T16:57:16.013 | database_errors | dba.stackexchange.com | |
135,698 | Complex key performance problem (MySQL, InnoDB) | A query is painstakingly slow in both production environment and (fortunately reproducable) on my local dev box. Production is Linux and my dev is currently Windows 10 with MySQL 5.7.11: [CODE] The tables are InnoDB. The query involves just one table and is generated by [CODE] ORM. Here is the table: [CODE] The table h... | For this [CODE] clause, I would try an index on [CODE] : [CODE] The [CODE] with e small [CODE] complicates things though, so a different order of the columns in the index might be better: [CODE] . | 1 | 3 | 137 | 2016-04-18T19:12:22.797 | database_errors | dba.stackexchange.com | |
1,080,224 | Nginx serve two services from same port from two files? | I have an nginx server file that serves some static content, looks something simple like: [CODE] I reuse this on a production server and a staging server. On the staging server, I want to front an API as well. If I just add another location in: [CODE] But then I have different server files for the different serves, and... | After reading the answer to this question ( Use "include" in nginx server block but where to save? ), I realized I could factor out my locations in a modular fashion via include files: [CODE] And then different locations can be added one-per-self-documentation-file. | 0 | 0 | 183 | 2021-10-11T17:54:23.333 | infrastructure | serverfault.com | |
299,489 | Problem with msiexec.exe locking up when installing / uninstalling | I am running two virtual 2008 Windows Servers that have been having some reoccurring problems for the past few months. Msiexec.exe seems to run and always freezes at 25% cpu usage and around 12 - 15k memory usage when uninstalling (and perhaps installing) certain applications. I first noticed this when trying to remove... | We had a similar problem with Server 2003 with Terminal Services. [CODE] would consume 25% CPU for an unusually long time during install/uninstall, but if we waited it would complete. Small [CODE] packages which should have taken seconds to install were taking 15 or 20 minutes. We found the problem was [CODE] bloat and... | 3 | 2 | 7,398 | 2011-08-10T02:35:47.907 | infrastructure | serverfault.com | |
665,739 | Forwarding a port on the loopback interface to a remote IP/port | I have two Docker containers that I'm trying to network together in a specific way. Container A is running a Redis server on port 6379. Container B is running an interactive shell and needs to access Redis. Using Docker's linking feature, a user inside container B can connect to Redis on through 10.1.0.2:6379, which tr... | I would use socat for that: [CODE] You might want to run this using supervisor or a similar tool. On ubuntu: [CODE] Now you can start/stop the redis-socat process using: [CODE] It will also automatically start at boot time. | 5 | 3 | 3,972 | 2015-02-07T02:23:05.167 | api_errors | serverfault.com | |
310,330 | Member vs. free-standing functions with respect to interface uniformity | Item 23 of Effective C++ (3rd edition) by Scott Meyers is titled: "Prefer non-member non-friend functions to member functions". The reason Scott suggests is the increase of encapsulation. So, only the functions that need to access the private members are made member functions, the other functions are made free-standing... | To directly answer the question you asked, I'd say the short answer is no: it's not necessarily worthwhile writing a wrapper for every member function, just to give a uniform interface. That said, it can be worthwhile to do so if you have something that corresponds closely to a concept, that's defined entirely in terms... | 11 | 5 | 4,021 | 2016-02-17T14:41:11.597 | api_errors | softwareengineering.stackexchange.com | |
361,827 | Should all methods of a class be at the same level of abstraction? | I have a class [CODE] (Just an example name) which has the methods [CODE] These methods can be used do do anything on the API but later I have added more methods which implement more specific tasks that I want to do in my application. Some of these new methods are [CODE] [CODE] [CODE] These methods provide a far higher... | Yes, in general, a single class should exist at a single level of abstraction. Having multiple levels of abstraction tends to violate the Single Responsibility Principle. And by just tacking on operations, you can build a sort of God Object, breaking down the cohesion of the class. And tacking on methods is pretty much... | 4 | 6 | 714 | 2017-12-05T01:30:23.467 | api_errors | softwareengineering.stackexchange.com | |
47,314 | ORDER BY items must appear in the select list [...] | Using Microsoft SQL Server 2008, I get the following error. Msg 104, Level 16, State 1, Line 43 ORDER BY items must appear in the select list if the statement contains a UNION, INTERSECT or EXCEPT operator. The query is I am using is kind of complex, but the [CODE] statement in side of the [CODE] clause can not see the... | If an alias is used in an [CODE] it must be used on its own, not inside an expression. If inside any kind of expression it tries to resolve it to a column in the base table sources not as an alias. So for example [CODE] Returns (ordered by alias) [CODE] But [CODE] Returns (Ordered by base table column [CODE] ) [CODE] Y... | 7 | 11 | 14,739 | 2013-07-30T20:57:25.880 | database_errors | dba.stackexchange.com | |
17,956 | Mac OS X machines - VERY slow access to Windows shares | I have a handful of mac boxes accessing a share from a remote Windows Server 2003 box over a site-to-site VPN. They are connecting to the share using cifs, authenticating with AD credentials, and performance is absolutely pathetic - think waiting 5+ minutes to open/copy/move shared docs, even small ones I am relatively... | My gut says you might be having an MTU issue on your VPN. Path MTU discovery is supposed to work around this, but there can be misconfigurations of networking gear that make it not work right. I don't know what the specific PING syntax is on OS/X, but on Windows you can send a PING from the server to one of the clients... | 3 | 1 | 3,649 | 2009-06-02T17:41:09.617 | infrastructure | serverfault.com | |
10,585 | IID violation in machine learning | Imagine I'm collecting some training data. Lets say I collect a 30minute time series from 1000 people so I have 1000 observations (rows) in my feature matrix. I train some model (lets say a neural net for this example) and I find my AUC is really poor and I believe the problem to be the fact that I only have 1000 obser... | Suppose you are investigating if heart rate can predict if a person smokes. You measure bpm for 30x1m consecutive times, and ask if the person smokes in order to build your training model data set. What would contribute to a better predictor? 30 observations from a person who smokes, or 1 observation from 30 people who... | 7 | 3 | 1,888 | 2016-03-07T23:03:06.100 | data_quality | datascience.stackexchange.com | |
630,837 | Under what circumstances is TCP-over-TCP performing significantly worse than TCP alone (2014)? | Many admins keep perpetuating - on ServerFault and elsewhere - how bad of an idea TCP-over-TCP is, e.g. in VPNs. That even the slightest packet loss will make one suffer from at least severe throughput degradation if not TCP meltdown, and that TCP-over-TCP is therefore strictly to be avoided. And that probably was once... | I think it's actually more debated than you make it appear. There is an admittedly old, related Linux FAQ: http://www.tldp.org/HOWTO/VPN-HOWTO/ I've used a PPP-over-ssh-over-ADSL for more than 12 years, and it never failed me, so from my experience I'd dare to say that the doomsayers probably largely exaggerate. TCP ov... | 31 | 8 | 6,786 | 2014-09-24T10:07:24.323 | airflow_errors | serverfault.com | |
402,653 | Layered Model-View-ViewModel design | I am designing an application using C# and Windows Presentation Foundation (WPF). I would like to follow (at least) the very basic rules of software architecture, like dependicies only going in one direction. Also I would like the UI layer to be without any sort of business logic (i.e. the application should work even ... | This looks properly strange to me. Normally, in MVVM, the only thing in your UI layer is xaml. Your View Models must not depend on your UI, so logically, they are a different layer (the reason for this is testability of your application independent of the UI, which is a very, very desirable attribute). There is not nec... | 1 | 1 | 1,021 | 2019-12-18T10:47:19.990 | api_errors | softwareengineering.stackexchange.com | |
558,615 | File modifications lagging behind | We are having a weird issue where file creation/removal from a NFS client takes a very long time to propagate out to the other client(s). Mount options we have on the clients are: [CODE] The export has: [CODE] We verify this by on one client doing: [CODE] And on another client we touch foofile (or rm it). Modifications... | I'm not going to answer your question directly. NFS clients are not guaranteed to see updates very fast. Yes, you can tune parameters to control the delay but the result will be worse caching (and therefore terrible performance) on the clients. Usually when I find myself needing NFS clients to see changes faster I take... | 1 | 5 | 511 | 2013-12-02T09:09:07.250 | infrastructure | serverfault.com | |
935,445 | Split duply/duplicity backup into subdirectories | I have been running backups with duply for a while now. This works great so far, but recently I started getting the error message [CODE] . I still have enough storage available, but the storage service I use for backup has a limit of 3000 files per directory. Is there a way to tell duply/duplicity to automatically dist... | you can try the multibackend , which is normally meant to combine various different backends, but you should be able to point it to different folders on the same backend as well. ..ede/duply.net | 0 | 0 | 128 | 2018-10-14T10:23:55.310 | database_errors | serverfault.com | |
529,288 | calculating days until disk is full | We use graphite to track history of disk utilisation over time. Our alerting system looks at the data from graphite to alert us when the free space falls below a certain number of blocks. I'd like to get smarter alerts - what I really care about is "how long do I have before I have to do something about the free space?... | We keep a "mean time till full" or "mean time to failure" metric for this purpose, using the statistical trend and its standard deviation to add the smarter (less dumb) logic over a simple static threshold. Simplest Alert : Just an arbitrary threshold. Doesn't consider anything to do with the actual diskspace usage. Ex... | 10 | 3 | 6,935 | 2013-08-07T11:01:39.040 | pipeline_ops | serverfault.com | |
446,858 | How to add multiple CA certificates to LDAP client | I'm having trouble with adding a 2nd LDAP server into the client configuration. If I configure the client to use just either one, it works fine. So I'm sure both CA certificates work. I have tried using TLS_CACERT option in both [CODE] and [CODE] , but it doesn't work. I get this error when I do an ldapsearch. This is ... | If you are using multiple ldap servers, sign the cert for all the LDAP servers with the same cacert. That way you only have to distribute only one cacert. | 5 | 0 | 2,136 | 2012-11-08T19:01:22.920 | infrastructure | serverfault.com | |
22,796 | Convolutional network for classification, extremely sensitive to lighting | I trained a convolutional network to classify images of a mechanical component as good or defective. Though the test accuracy was high, I realized that the model performed poorly on images which had slightly different lighting. The features that I'm trying to detect are subtle, and lighting seems to trip the model into... | It's called overfitting, your model learned to predict labels based on features which are not actually responsible for particular predictions, so when they are not presented it fails to predict right. Although there are various ways to deal with overfitting (e.g. Dropout) what you seem to need is image augmentation. It... | 9 | 2 | 528 | 2017-09-03T15:04:51.820 | data_quality | datascience.stackexchange.com | |
14,677 | How to approach Multilingual Text Classification? | The company I'm working for runs social network sites, and we're classifying messages sent one-to-one as spam or not spam. The issue is that it's been trained exclusively on German training data, since most of the networks we operate are local to Germany. Soon we will need to support multiple languages for this, since ... | In a similar situation, -after trying some alternatives- I had to build a language classifier in front of all learning and classification steps. That is, for learning: Detect the language of the input (say, an enumeration like "DE", "EN", etc.) Apply language specific stemming to the words of the input. Prepend words i... | 1 | 3 | 4,319 | 2016-10-21T08:42:44.307 | data_quality | datascience.stackexchange.com | |
532,930 | ESXi 5.x unable to start sfcbd for hardware monitoring | I've been trying to configure my ESXi server to take advantage of hardware monitoring via iLO drivers. However, no matter what I do to try and start the sfcbd service, I get a list of menu options. I'm running [CODE] and this returns a list of command-line switches to add to the command (none of which work). It makes m... | I don't understand what the [CODE] service has to do with any of this. If you wish to monitor a Gen8 ProLiant server through the ILO-only, you only need the HP AMS Offline bundle to be installed on the host. Edit - You're using a G7 ProLiant. Agentless Management is only supported on ILO4 and Gen8 systems. If you're in... | 1 | 2 | 4,546 | 2013-08-22T12:46:27.980 | data_quality | serverfault.com | |
34,154 | How can I access user files on a disk moved from a Windows 7 machine to an XP machine? | I moved the hard drive from one machine (Win 7) to another (XP) and now certain folders tell me "Access denied". I am logged in as an administrator. I had a different account on the other machine. Neither account authenticated to anything besides the local machine. The old machine is apparently dead, so I can't do anyt... | Can you try to edit the Access Control lists directly? Make sure "use simple file sharing" is disabled in the folder options, and then do: right click->security and edit the ownership of the files/directories. In Windows, file ownership is not determined by usernames, but by security identifiers (SID), and these are di... | 2 | 1 | 1,027 | 2009-06-30T22:54:32.277 | infrastructure | serverfault.com | |
253,725 | Removing duplicates (deduplifying) from an existing, huge, table | I have a huge table. Each row has an ID, some columns which relate to that ID specifically, a short (DNA) Sequence, and some columns which relate to that sequence particularly. If these have not yet been calculated (for this row) then they are null, but the calculations will always come out identical for a given sequen... | Yes, the delete step is going to be a pain and might cause (slight) performance issues, but see here for a ray of hope in that regard. The best solution (prevention is better than cure) is to create a UNIQUE index on your dna field (or whatever you call it) and then this problem cannot arise in the future and the steps... | 0 | 3 | 1,432 | 2019-11-20T13:19:06.073 | data_quality | dba.stackexchange.com | |
168,939 | Can SQL Server start taking backups by itself? | We have a SQL Server which started to take backups by itself every now and then. It started for a few days ago. When it fails an error is logged saying that source is "Microsoft SQL Server Native Client 10.0" It also says: "SQLSTATE: 42000, Native Error: 3201 Error state: 7, Severity: 16 Error message: Cannot open back... | Most likely it is a 3rd party backup solution such as NetBackup that your sysadmins have pointed to your instance. Try reading the default trace to see if the application name column gives you the specifics: [CODE] | 0 | 2 | 188 | 2017-04-03T11:49:57.787 | database_errors | dba.stackexchange.com | |
40,957 | How to determine cause of runtime increase given two query plans with SpillToTempDb warning | Two actual query plans were captured for two executions of one query: Plan "Fast" took ~1s and occurs about 90% of the time. Plan "Slow" took ~16s. Since the graphical plans look identical to me, I dumped the XML versions and performed a diff to look at the text differences to be sure. There are 2 "SpillToTempDb" warni... | The cost is the same (1%) for both the slow and fast cases. Does that mean the warning can be ignored? Is there a way to show "actual" times or costs. That would be so much better! Actual row counts are the same for the operation with the spill. The cost shown is always the optimizer's estimated cost of the iterator, c... | 3 | 6 | 1,003 | 2013-04-25T23:44:37.873 | database_errors | dba.stackexchange.com | |
278,681 | Windows Update checking/downloading new updates hangs Windows 2008 R2 Enterprise with TMG installed | We have weird situation with Windows 2008R2 and TMG 2010 installed. It happened two times already on 2nd Tuesday of the month that Windows dropped all connections (VPNs, routing etc) and when trying to log in remotely / locally to it you could only see welcome screen and it never logs you in (I have even waited 30 minu... | It seems the problem is related to [CODE] between AD and TMG. Whenever the AD clock and TMG clock differs for 5 minutes (Kerberos setting can be changed to allow more time difference) it makes TMG unresponsive. Took us some time and "hangs" to figure it out! Hope this helps someone else :-) | 1 | 1 | 5,519 | 2011-06-09T12:27:03.560 | infrastructure | serverfault.com | |
32,345 | Initial embeddings for unknown, padding? | Last time I've been passing pretrained word embeddings into LSTM to solve text classification problems. Usually, there are additional [CODE] , [CODE] replacements for padding and unknown types. Of course, there are no pretrained vectors for them. Solutions I've come up with are Fill them with random values Fill them wi... | In my experience, what works well is : For padding, fill a zero vector embedding (as pixel intensity in image data padding) is the only and best solution. For words that don't have a pre-trained embedding, you should try to train them: as you do, fill them with random values when initializing, but set them to trainable... | 5 | 2 | 6,093 | 2018-05-29T20:07:26.047 | data_quality | datascience.stackexchange.com | |
819,669 | Elevate to administrator privileges in CMD/Powershell without UAC? | I managed to change the port or remote desktop on my Windows Server 2016, using REGEDIT. But the problem began when I forgot to open that port in the firewall, so therefor I can no longer access remote desktop. The server is still running a website that can run PHP code, and a java minecraft server, and I have FTP acce... | Just an untested hacky attempt... Using netcat to portward.. Upload 3 files via FTP fpipe.exe ( http://www.mcafee.com/us/downloads/free-tools/fpipe.aspx ) forward.php forward.bat Content of forward.php: [CODE] content of forward.bat (replace 8888 with your new RDP port) [CODE] Visit forward.php via webbrowser and then ... | 0 | 0 | 3,059 | 2016-12-08T22:55:58.630 | database_errors | serverfault.com | |
222,864 | PostgreSQL 8.4 - Tablespace Optimization | I'm currently running a PostgreSQL Database with about 1.5 billion rows / 500 GB of data (including indices). There are several schemata: on for the (read only, irregular changes / updates) 'core-model' and one for every user (about 20 persons). The users can access the core and store data in their own schema, so every... | Definitely more important to move the WAL files if you haven't already done so. Don't start moving individual tables until you have to - especially if the speed of the disks are more or less equal. | 2 | 2 | 457 | 2011-01-15T17:00:06.897 | api_errors | serverfault.com | |
243,961 | RDP Acceleration | Possible Duplicate: How to get Faster RDP HI Does anyone have experience of any good RDP Acceleration software / hardware. We are running over 250 terminal server connections to hyper-v servers and when our users access Flash or PDFs the lag is really bad. Thanks | Is msiexec.exe getting kicked off when they open a PDF? Slow performance even for a plain text based PDF that has no multimedia? What OS? Disable javascript in any PDF reader as javascript makes it so much more vulnerable. | 2 | 0 | 2,402 | 2011-03-06T21:12:08.457 | data_quality | serverfault.com | |
439,388 | Kernel Logging disabled? | [CODE] And start ups: [CODE] But when I installed CSF/LFD I am getting nothing. LFD does not create lfd.log and nor are any blocks being logged in /var/log/messages either from the firewall. This is not natural. I looked for klogd but maybe I am looking in the wrong place for it to see if it is enabled? [CODE] Also not... | You have a [CODE] -- look into [CODE] to see which filters might apply and which destination logfiles are used for kernel messages. | 0 | 1 | 1,023 | 2012-10-17T15:38:56.277 | infrastructure | serverfault.com | |
373,919 | Mysql dump restoring | I ran into a big trouble. I made mysql dump using version 5.0.77 without setting the compatibility mode (I wasn't aware of this problem). Actual mysql server is version 4.0.18. Today our database crashed. Lots of tables lost. While trying to restore the dump, it's returning error "ERROR 1193 at line 18: Unknown system ... | It may well be worth installing, on another box if required, mysql 5.0.77, restoring, and then re-dumping with the appropriate options. This isn't an elegant solution, but if you're in "big trouble" and need something that works and fast, this is the first thing that jumped into my mind. | 1 | 2 | 2,916 | 2012-03-27T13:05:01.187 | database_errors | serverfault.com | |
1,004,701 | firewall-cmd not allowing loopback redirect | I am trying to redirect a port on the loopback interface, but it does not seem to be working [CODE] but when I run [CODE] I get connection refused. [CODE] can connect fine. Any advise for how to get this set up correctly? Thanks | firewalld installs a rule in the [CODE] chain of the [CODE] table. This table is consulted only for foreign traffic. Locally generated traffic traverses the [CODE] chain of the [CODE] table, so you need to install a rule with: [CODE] | 1 | 3 | 3,835 | 2020-02-26T16:20:41.887 | api_errors | serverfault.com | |
66,894 | How to redirect subdomain to domain with subdomain as parameter | I would like to redirect my wildcard subdomain to my main domain using the subdomain as a GET parameter in the URL using [CODE] . Example of what I would like to happen: [CODE] redirects to [CODE] Here is the current rule I have put together based on other answers on this site: [CODE] However, when the redirect happens... | After trying to solve this using .htaccess and failing, I ended up using PHP to do the URL parsing for me. For those who wish to see what I did: $host = $_SERVER['HTTP_HOST']; $subdomain = str_replace('.example.com', '', $host); if($subdomain != 'www') header("Location: http://www.example.com/shop?user_name=".$subdomai... | 2 | 0 | 7,503 | 2009-09-19T02:53:54.497 | infrastructure | serverfault.com | |
999,854 | Can I redirect all of the NDRs for my domain to a central mailbox in Exchange Online? | At my company our ticketing system pulls from dedicated mailboxes, but when an email is sent from one of them due to some automated process or other and fails it of course throws an NDR. The problem is that those NDRs trigger new tickets. What I want to do is redirect all of the NDRs from our various departments to a c... | Connect to Exchange Online via Powershell and run [CODE] Would set it to a shared mailbox address and assign rights to it from your helpdesk/support mailbox for visibility. You can also set it to $null and not receive any NDRs which is the default setting [CODE] Further reading on the Set-TransportConfig command | 0 | 0 | 2,085 | 2020-01-21T22:15:08.083 | infrastructure | serverfault.com | |
827,317 | How to stop apache2 on ubuntu - no process visible | I just installed ubuntu 16.04 and apache2. The default config page shows up even if I stop apache2. This is absolutly strange as there is no process httpd. The server keeps serving the default file and altering the file shows the changes. This is the output on console: [CODE] What could be the problem here? | First of all, apache process on Ubuntu is named [CODE] not [CODE] as in CentOS. So, you need to verify it is stopped using: [CODE] Also, you need to confirm that no process is listening on port 80 using: [CODE] Another thing to confirm, look at apache2 access log to verify you are hitting this machine not any other one... | 0 | 0 | 788 | 2017-01-19T15:09:29.470 | infrastructure | serverfault.com | |
28,682 | Unable to call method in main class | I am trying to call a method in the main function using selenium. However, I am not able to do so. Getting null pointer error. The subclass [CODE] should be called in the main class [CODE] . Could someone please help me. Superclass: [CODE] Subcalss: [CODE] Error: [CODE] | It looks like the 'driver'-field in the 'Drinks'-class is never initialized. Hence the null pointer when you try to use that object on line 13. One way to fix that is to pass the driver object from Coop_main to the Drinks class as a constructor argument. Create a constructor in Drinks [CODE] Adjust Coop_main [CODE] Add... | 0 | 2 | 1,726 | 2017-07-20T10:51:04.593 | data_quality | sqa.stackexchange.com | |
127,857 | should the same machine key be used in development and production environments? | Our production servers all have the same machine key. However, our production and development systems do not have identical machine keys. We get heaps (about one per second) of exceptions of the form [CODE] We deploy the code after a build, .cs source is not present on production. aspx files are present on production. ... | The answer is no. The reason for not using same machine keys is that developers should not see production environment secret keys. If you have an ex-workers or external consultants, you can't guarantee that they won't spread the development code to somewhere. In wrong hands, the keys make it easy to attack to the serve... | 2 | 2 | 1,715 | 2010-03-30T20:44:14.693 | pipeline_ops | serverfault.com | |
244,637 | Reporting defects in Agile | I am working in sprint. At the end of sprint I need to send a defect report per sprint. Considering the below scenario please let me know your views. Two teams(A & B) are working at different locations in Sprint-2 and I am a tester from Team-A and report the defects for the items developed by Team-A in each sprint Ques... | I think there's a fundamental issue with the definition of 'done' in your example. If a 'defect' is identified within a sprint, I'd argue that there is no defect. The item is simply not 'done' and should be re-worked until it is. I would amend the definition of done to include the requirement that items have no known d... | 2 | 7 | 2,412 | 2014-06-11T07:42:48.130 | api_errors | softwareengineering.stackexchange.com | |
41,645 | mysqlslap chokes on strings that contain ";" delimiter? | I'm having a problem passing preexisting files full of SQL statements into mysqlslap. For example, I have a file named [CODE] that contains my table structure (as dumped by [CODE] ), with normal ; delimiting. I also have a file called [CODE] (actually a slightly munged general-log-file , but this is a tiny example that... | Give it up. Because (as Michael pointed out) mysqlslap is using naive string finding instead of a parser for the delimiter, if the delimiter you pick is anywhere in your --query or --create datasets, you're hosed. Instead, open up the mysqldump file, and merge any multiline statements into one line and let mysqlslap co... | 1 | 1 | 1,693 | 2013-05-07T00:54:52.343 | database_errors | dba.stackexchange.com | |
557,413 | Import SQL Dump from Command Line | I have an SQL Backup that has hundreds of individual databases inside of it. The backup is around 70GB in size and I have spent countless hours attempting to restore it on a new machine due to the previous one becoming corrupted. I am currently trying to restore this by doing... [CODE] As soon as I run this, the SQL ba... | You are redirecting the wrong way. Your command, as written, writes stdout of the mysql process to your .sql file. Give that angle brace a 180 degree spin and give 'er another try. | 1 | 2 | 178 | 2013-11-26T02:45:16.750 | database_errors | serverfault.com | |
697,786 | Selling my Used Servers online? | I am new here and doing a bit of research. I am running a startup which takes used technology, fixes it up and sells it online. I am looking for the best method/place to sell servers online, both new and old. Does such a place exist? Are there differences between corporate and hobbyest? Thanks in advance! Jes | You're late to the game. Ideally you'd have your own retail site, in addition to a presence on eBay. But why would someone buy from you when Tier-1 manufacturers already sell refurbished equipment? | -5 | 2 | 67 | 2015-06-09T20:58:04.487 | infrastructure | serverfault.com | |
80,292 | Replicating tables from LAN database to web server? | I have an in-house database (that's actually part of a third-party product) running on 2008R2 Express. We'd like to display some of the data on a new website we're working on (running 2008R2). I'm more developer than administrator, so I'm wondering the best method for getting data from one to the other. Data doesn't ha... | There are a variety of ways you can do this. If you only need a portion of the database, you can have copies of the tables which you refresh on the destinations periodically. The idea is that you have your users reading one copy of the data, then you have an identical table in a different schema, and you reload that co... | 0 | 1 | 59 | 2014-10-15T21:26:29.820 | database_errors | dba.stackexchange.com | |
246,729 | Why do programmers still use "SAFE_DELETE"? | If I had a dime for every time I've seen this macro in use, today I would be coding just for fun: [CODE] Why do programmers insist in keep using this macro when [CODE] checks for null? Is is because it sets the pointer to null at the end? Then why not at least rewrite it and remove the redundant check: [CODE] Still, it... | Let me put it this way. Does it seem like something C++ would do? C++ is replete with gotchas and undefined behavior, but in this one instance, it helpfully validates a parameter for you? Every other "safer" language you know throws an exception if you try to do anything with a null pointer, but the unsafest language y... | 3 | 12 | 3,305 | 2014-07-03T00:01:36.523 | api_errors | softwareengineering.stackexchange.com | |
41,367 | Replacement HDDs for IBM xSeries | One of the servers I inherited in my current position was marked to be decommissioned, as it has been replaced by a new server (everything has already been moved across). The first problem I faced was the poor performance of the ERP package. It turns out that the new server is actually a significantly lower spec than t... | I've replaced vendor-provided SCA disks with generic ones on Sun, HP and IBM boxen, with no technical issues at all. Generally the vendor disks are just generic disks from Seagate, Fujitsu etc with an vendor sticker slapped on, and a 200% markup. Note that using a non-vendor supplied disk, memory or other component may... | 1 | 2 | 3,628 | 2009-07-16T01:42:52.090 | infrastructure | serverfault.com | |
214,769 | How to reference primary key when inserting in MySQL | I have a database containing the tables [CODE] and [CODE] . I don't know how to correctly assign the foreign key in the [CODE] table. I read the information provided in this link and have constructed my DDL queries as follows: [CODE] Is this the correct way to create a foreign key relationship between my [CODE] and [CO... | You need to declare the column itself, so the books table should look like: [CODE] I added NOT NULL on columns title and genre since I believe they are mandatory in most situations. I would say that you also need something that uniquely identifies an author in real life, let's assume name does: [CODE] Now you can inser... | 1 | 0 | 777 | 2018-08-13T10:38:27.167 | database_errors | dba.stackexchange.com | |
72,221 | Display posted on date and time like1 hr ago or 30 min ago | I want to show the posted date like 1 hr ago, or 30 min ago. This is my code: [CODE] I am getting a problem when the posted time is 11:50 and the server time is 12:10. In that case, I would like to show "20 min ago", but my code showing 1 hr ago. | As I said in the comments above, this should really be formatted in the application layer, where you are controlling the presentation to the user. The issue lies with the way SQL handles the [CODE] function, in that comparing the [CODE] difference between 08:59 and 09:00 will result in 1 hour, because the hour has tick... | 4 | 6 | 4,786 | 2014-07-24T06:58:20.847 | warehouse_errors | dba.stackexchange.com | |
1,025,719 | How to downgrade back to an older version of postgresql | I upgraded to OSX Catalina, and in the process of fixing broken packages managed to inadvertently upgrade [CODE] from version 11 to version 12. When I try to start [CODE] I see the following in the log: [CODE] How do I remove version 12, and then reinstall version 11? I am not sure which which minor release of version ... | You can run [CODE] to upgrade the databases from a previous version retaining all data. Information per: brew info postgres If you really want to downgrade then [CODE] would do that. | 4 | 6 | 27,626 | 2020-07-18T08:07:04.450 | database_errors | serverfault.com | |
997,261 | TLS certificate name for the target of an SRV DNS record | When setting a DNS SRV record like [CODE] , why has the TLS certificate name on [CODE] to be [CODE] and not [CODE] ? I've read on what names for TLS certificates when using SRV records that it's to prevent man in the middle attacks but I'm not sure to understand why: MITM attacks on the DNS would be prevented using DNS... | this could be implementation dependent answer. But in general it would work based on the options used for the "redirection" in DNS : CNAME : The client's request is redirected - the originally requested FQDN would be presented in the destination certificate as the redirection is done during the original request. SRV re... | 0 | 0 | 498 | 2020-01-01T10:33:30.557 | infrastructure | serverfault.com | |
856,748 | Selenium ChromeDriver makes blank screenshots | In jenkins taken screenshots are blank or invalid like in example here: Maybe someone knows what kind problem could be with it? Locally everything works fine WebDriver.ChromeDriver.win32 version - 2.30.0 Selenium.WebDriver version - 3.4.0 Code: [CODE] | It seems that this issue happened before. Check this: https://bugs.chromium.org/p/chromedriver/issues/detail?id=476 It's probably bug in new chromedriver 2.30. I had the same issue and the workaround is to connect to VM by Remote Desktop Connection. Problem only occurs when you use selenium remotely and noone is connec... | 5 | 2 | 11,606 | 2017-06-20T07:05:58.247 | pipeline_ops | serverfault.com | |
116,682 | Cannot see physical/logical cores of newly added second quad-core when in Hyper-V manger | We have a DL380 G6 that was running with a single quad xeon. Since hyper-v is going well, we wanted to add more VM's. To keep things from bogging down, we added a second quad xeon to the box, and doubled the memory. When I create a new VM, logical cpu's only shows 1-4. I was expecting to see a choice of 1-8. When I loo... | According to this MSDN blog : Virtual Processor support: Up to 4 virtual processors per virtual machine So it seems that you may only be able to allocate up to four virtual processors per VM. | 0 | 1 | 97 | 2010-02-25T10:55:20.623 | infrastructure | serverfault.com | |
255,420 | What properties does an object oriented language have? | I'm currently working on a game and wanted to add some scripting support. Due to trying to keep the entire codebase in managed c# (Excluding Monogame), I am using a custom language for the scripting (No managed only implementations of Lua exist...except AluminumLua which is incomplete). In such a language, basic provis... | The core idea behind object-oriented programming is the encapsulation and information hiding of data and functions that operate on that data within objects . Rather than building an open data structure (think traditional C [CODE] ) and passing a pointer around to functions, you put the functions in the structure and ca... | 2 | 1 | 460 | 2014-09-05T00:20:22.153 | api_errors | softwareengineering.stackexchange.com | |
197,277 | 10.1.31-MariaDB keeps restarting no errors nor warnings | This was happening before, but it started happening more frequently since I switched all of my databases to InnoDB storage engine. This is a log [CODE] This is my.cnf [CODE] As I see no errors or the real reason this could happen it looks like i'm running out of mememory I recently upgraded I have 8GB of ram.. These hi... | Things to do in [mysqld] section of my.cnf [CODE] SET @max_allowed_packet=1000000000 # for a 1G size, abbreviation not allowed 1G is the max tolerated according to refman [CODE] | 2 | 1 | 2,775 | 2018-02-07T13:48:17.577 | database_errors | dba.stackexchange.com | |
167,781 | PostgreSQL/Psycopg2 indexing array in the size of thousands | I will have an array the size of 16,380, and I want to index them so I can call aggregate functions over them using 16,380 indices. For example, I have a table: [CODE] I want to select all the values from large_array_of_values column with specific index, say index 15,123 and apply an aggregate function such as populati... | I dont' think indexes will help. I am not sure why, but I am just being experimental... First, we create a table with your structure, and fill it with random data (10.000 rows, and a vector of 1.000 columns). [CODE] At this point we create one sample index for values at index [32] of the vector (plus the id!): [CODE] N... | 3 | 4 | 330 | 2017-03-21T18:46:02.567 | data_quality | dba.stackexchange.com | |
147,042 | pt-table-checksum to compare two tables? | I'm trying to find a way of comparing two tables in two databases (master and slave), as I have applied some slightly different settings to one, and need to see what affect it has (if any) on the data etc. Ordinarily I would use [CODE] which has worked well in the past, but this doesn't seem to have the option for a si... | If you have a Windows workstation and have odbc driver to MySQL, then you might try my utility - there is a free edition. Maybe it will help you. https://selectcompare.com | 2 | 0 | 1,601 | 2016-08-17T09:17:37.423 | database_errors | dba.stackexchange.com | |
534,863 | Set group permission on folder | I have a folder with lots of subfolders D:\Data\Subfolder1 D:\Data\Subfolder2 D:\Data\Subfolder3 D:\Data\Subfolder4 D:\Data\Subfolder5 ... I need to create three active directory groups for each subfolder like this. FS_Data-Subfolder1_Read FS_Data-Subfolder1_Change FS_Data-Subfolder1_Full and after this is done i have ... | See if this example from Don Jones helps you: You basically take the existing acl object from the folder, add a new rule to it (SetAccessRule), and the rule contains the principal(user or group,the right and whether it's an allow or deny). The updated aclobject is then applied to the file/folder using set-acl. [CODE] | 0 | 2 | 3,945 | 2013-08-29T15:08:44.203 | infrastructure | serverfault.com | |
100,134 | How does using another agents action choice impact the efficacy of learning with Deep Reinforcement Learning | I am doing a project where I have multiple soft actor-critic sub-agents learning at the same time in an environment using shared experiences. Each sub-agent selects an action using their own policy, the overall agent combines these into a single action choice which gets submitted as the action. The environment gives ea... | In short, the answer is yes, your intuition is correct. The problem you are trying to solve is a Multiagent Reinforcement Learning problem and single-agent approaches don't work well here. One of the main obstacles is the non-stationary transitions of the environment's states. There are various settings (e.g. competiti... | 0 | 1 | 59 | 2021-08-16T09:05:22.723 | data_quality | datascience.stackexchange.com | |
256,330 | Temporary hosting of a web app | I need to host a web app for a job application. The app is dependant on an Apache Module, meaning my regular webhost (Dreamhost) cannot support it. My private internet connection also isn't an alternative. I was thinking about hosting it on a VPS somewhere. Suggestions for a VPS host that maybe has a trial period? Or o... | It might be worth having a look at amazon's free offering for EC2 http://aws.amazon.com/free/ If it is for a job application then being able to throw in the fact you are familiar with popular "cloud" platforms such as AWS never hurts. | 1 | 2 | 179 | 2011-04-06T12:25:10.077 | infrastructure | serverfault.com | |
376,378 | Problem with async/await pattern -- in C# and JavaScript -- how to return sync value | In old-style await'less NodeJS, when you call a function that had an asynchronous aspect, you'd pass in the well-known callback which gets called when the asynchronous portion is done. This didn't pollute the return value of the function whereas the function can still return something meaningful to the caller synchrono... | Why can't you return an already completed task? C#: [CODE] JavaScript: [CODE] In fact, C# recently added [CODE] to avoid allocations for this scenario where a value is available immediately. | 1 | 3 | 1,552 | 2018-08-04T01:47:26.903 | api_errors | softwareengineering.stackexchange.com | |
307,060 | What is causing my web service call to timeout? | The web server is Windows Server 2003 with IIS 6. The web service is an ASMX running in .NET 4.0. When calling the web service as the domain user named 'ALBERT' everything works successfully. [CODE] When the exact same call is made using the domain user 'DALRYMPLE' the request times out. [CODE] The same PC is used on t... | I suspect MTU, try picking it up or down by 1. see if it changes anything, QA for further issues and set it to a value that will not break. | 1 | 1 | 3,669 | 2011-09-01T00:37:25.007 | infrastructure | serverfault.com | |
28,948 | Determining whether column in view can only contain unique values | I have a SQL Server 2008 database with several views. I'm looking for a way to definitively determine whether a particular view has a column that can only contain unique values (i.e. can be used as a primary key). Some of these views have simple definitions, but some are also quite complex, so I find that manually anal... | Short answer: you'll have to do your own dirty work. Like @mrdenny says, there is no way of automating this task. Very long answer: SQL Server doesn't have an easy way of determining unique columns in a view, in part because of how complex (and dynamic) views can be. There are two methods to make a first approximation ... | 4 | 3 | 3,796 | 2012-11-19T23:08:19.757 | data_quality | dba.stackexchange.com | |
1,742 | How to insert (file) data into a PostgreSQL bytea column? | This question is not about bytea v. oid v. blobs v. large objects, etc. I have a table containing a primary key [CODE] field and a [CODE] field. I'd like to enter data into the [CODE] field. This can, presumably, be done by one of the [CODE] languages, and I may look into doing this with [CODE] in the future. As I am s... | as superuser: [CODE] [CODE] was introduced in 9.4 so for older versions you would need: [CODE] then: [CODE] | 57 | 38 | 213,282 | 2011-03-14T20:38:14.003 | database_errors | dba.stackexchange.com | |
290,285 | What is a simple way to let a user select a folder from a tree? | I have a Python-Flask app in which users can place files into a folder. As of now the directory structure is something like: [CODE] The user can create directories and subdirectories within [CODE] to organize files. So far I am making AJAX calls to the server to get details of folders etc. and populate a dropdown list ... | Clearly, you have to make server requests at some point to get the user's stuff. For optimal UX, assuming it's impractical to load everything upfront, it'd be silly not to use some kind of AJAX request. So the real question is: What should the granularity of your requests be? The correct answer has more to do with UX t... | 0 | 2 | 170 | 2015-07-21T03:53:57.773 | api_errors | softwareengineering.stackexchange.com | |
328,628 | How to - UDP NAT traversal using BSD sockets | I have been reading the NAT traversal requiring the use of an external STUN server. There are few public STUN servers but I do not know how to use them to find out my public IP that can be used by the other client to initiate the connection. Being a noob in this, I am not able to find out the correct documents for this... | It's in the STUN bind response. RFC 5389 , the STUN specification, explains how on page 7: The STUN server copies that source transport address into an XOR-MAPPED- ADDRESS attribute in the STUN Binding response and sends the Binding response back to the STUN client. As this packet passes back through a NAT, the NAT wil... | 1 | 1 | 302 | 2011-11-07T20:12:34.593 | infrastructure | serverfault.com | |
31,463 | Evaluation metrics for Decision Tree regressor and KNN regressor | I have started working on the Decision Tree Regressor and KNN Regressor. I have built the model and not sure what are the metrics needs to be considered for evaluation. As of now I have considered Root mean squared error. Can we use $R^2$ values for Decision Tree and KNN or is it applicable only to Linear Regression Mo... | Generally when ever we are trying to compare between models and to choose the best one, we go for other metrics like AIC , BIC , AUC (this is not applicable as it is used for classification algorithm) etc along with $R^2$ . Now why are they important criteria because AIC tries to select the model that most adequately d... | 3 | 4 | 7,110 | 2018-05-10T01:52:35.937 | data_quality | datascience.stackexchange.com | |
1,128,400 | Nginx doesnt' log into access.log | I'v been struggling with Nginx logging. A problem that I found out first was logrotate failure. so I've changed user to the same owner of nginx worker process which is www-data and I forced logrotate, then It suddenly stopped to log. here's the permission [CODE] and this is the logrotate configuration: [CODE] | This is quite overengineered. [CODE] Basically the line su www-data adm is the one you're missing. Also note that when creating new vhost config and doing [CODE] - nginx will create new access/error logs (if defined) from root, which will effectively stop their rotation in the future. | 0 | 0 | 317 | 2023-04-11T06:04:59.853 | infrastructure | serverfault.com | |
227,421 | logrotate pattern matching for daemon restart | In a setup very much like: http://wiki.apache.org/httpd/ExtendingPrivilegeSeparation I have logs located in [CODE] I would like to use logrotate to rotate these logs 50M, gzip the rest, and keep 5. Instead of repeating the same section over and over again, I'm wondering if I can use something like: [CODE] to match the ... | I think the [CODE] man page answers this question quite nicely. | 0 | 0 | 479 | 2011-01-27T01:03:57.727 | infrastructure | serverfault.com | |
211,543 | Defining and overriding open and closed intervals | I have been considering the following situation as part of documenting and interface ( [CODE] ) and an implementation ( [CODE] ) of that interface. The interface [CODE] contains methods which involve the following two arguments: A percentage , passed as an integer. A name , passed as a string. The valid values for the ... | I don't believe there's a specific name for it, you'll probably have to write it out, e.g.: The minimum length of [CODE] must be 1. There is no strict maximum length, but any implementation must support a maximum length of at least 100. This is more concise, although somewhat less clear: Any implementation must support... | 1 | 1 | 59 | 2013-09-13T20:58:23.523 | api_errors | softwareengineering.stackexchange.com | |
406,606 | Postgres error message: FATAL: Ident authentication failed for user "..." | Say you're seeing this message: [CODE] What are the causes of this error message? | It means that Postgres is trying to authenticate a user using the Ident protocol, and can't. Ident auth automatically matches Unix usernames with Postgres usernames. It works like this: You have database role 'foo' on database 'db' Your [CODE] file (in [CODE] ) defines 'Ident' as the protocol to connect to database [CO... | 50 | 66 | 176,230 | 2012-07-11T00:44:23.417 | api_errors | serverfault.com | |
629 | Passing array parameters to a stored procedure | I've got a process that grabs a bunch of records (1000's) and operates on them, and when I'm done, I need to mark a large number of them as processed. I can indicate this with a big list of IDs. I'm trying to avoid the "updates in a loop" pattern, so I'd like to find a more efficient way to send this bag of ID's into a... | The best ever articles on this matter are by Erland Sommarskog: Arrays and Lists in SQL Server 2008 - Using Table-Valued Parameters Arrays and Lists in SQL Server 2005 and Beyond- When TVPs Do Not Cut it Arrays and Lists in SQL Server 2000 and Earlier He covers all options and explains pretty well. Sorry for the shortn... | 69 | 53 | 318,285 | 2011-01-14T19:05:04.067 | database_errors | dba.stackexchange.com | |
292,115 | WinServer 2003: Cant find process holding onto ports | We have a couple of production WCF services failing to start because their ports are apparently in use by another process. I have done a netstat -ano and found the PID's that are using these ports, which are all in the LISTEN state. The ports for endpoints/services hosted in the same processes all have the same PID's, ... | You can use SysInternals' TCPView ; it doesn't require any installation, you can simply run it without having to install anything (which is also true for Process Explorer, BTW). TCPView is also able to forcibly close connections and listening sockets. | 0 | 1 | 209 | 2011-07-20T05:57:58.180 | infrastructure | serverfault.com | |
915,327 | Unable to push after setting git smart http. Pull and Clone working | I am trying to set up git in my server with smart http as the access mechanism. Due to some intergration problems we can not use any other mehtod and it has to be the http or the https methods. So i followed a bunch of blogs/articles and managed to get the thing running. However now even though clone and pull are worki... | Chances are, git backend wasn't able to write to given directory, and then just hung (verify with ps -ef|grep git). This might have damaged the repo, so further pushes fail. To make it work 1) entire directory tree has to be owned by git.www-data, and writable by group (chown -R git.www-data, chmod -R go+rw) 2) create ... | 3 | 1 | 827 | 2018-06-05T18:49:06.827 | infrastructure | serverfault.com | |
258,005 | Virtualized SQL Server hits 100% CPU and 0 Active Memory | We recently experienced an odd crash with one of our server. We know what caused it, but we don't know why SQL Server responded the way it did. SQL Server 2016 Here is what happened: Friday: Changed MAXDOP from 4 to 2 without checking how much of an impact this would have on compiled queries. Saturday Morning: Server p... | Check out this interesting post from David Klee: VM Memory Counters Lie for SQL Server VMs In particular, this quote is very relevant to your situation: SQL Server uses memory as a working set I/O buffer, and memory blocks in the SQL Server buffer pool are most commonly used as a read cache. Memory blocks that are repe... | 3 | 2 | 533 | 2020-01-22T21:14:31.067 | api_errors | dba.stackexchange.com | |
140,406 | Simple PL/SQL code to throw NO_DATA_FOUND exception | In a recent interview I was asked to write a simple PL/SQL code to throw NO_DATA_FOUND exception without actually raising it from the code. I am wondering what could be a simple pl/sql snippet to do so. Probably using dual? | Many ways, but as you suggested, you can use [CODE] : [CODE] It'll produce a [CODE] when [CODE] d. | 0 | 1 | 408 | 2016-06-04T19:03:40.790 | warehouse_errors | dba.stackexchange.com | |
189,943 | Are there any practical uses of allowing recursive inclusion of a file? | I am currently implementing NASM-like preprocessor for my assembler, and I am wondering what is the correct way of handling recursively included files. From what I see, there are two ways to deal with it without hanging the preprocessor or even the OS: Set maximum include depth. Disallow including a file recursively (n... | The Boost.Preprocessor library extends and abuses the C/C++ preprocessor in strange and wonderful ways. One of its features is file iteration , which lets you #include a file multiple times with different macros #define'd each time, and they note that it can be useful (and is supported) for a file to iterate over itsel... | 2 | 2 | 293 | 2013-03-09T17:08:00.643 | api_errors | softwareengineering.stackexchange.com | |
322,486 | Nginx external POST returns 302 | I have a server setup with [CODE] + PHP-FPM + APC. On this server a [CODE] installation is running. What I'm having trouble with is that the callback from the payment provider is a POST and Nginx returns a 302 which makes the callback fail. This is the config file for Nginx for the site: [CODE] When the callback is mad... | Probably you are passing callback url to your payment provider without www prepended so it gets redirected by your first rewrite rule. BTW, don't use such rewrite to redirect to www host, use different [CODE] blocks with different [CODE] instead, see nginx documentation . | 1 | 1 | 3,637 | 2011-10-18T10:09:35.737 | database_errors | serverfault.com | |
1,063,875 | Workaround for Tomcat 9.0.46 (bug 65308) - NPE in JNDIRealm | Anyone been hit by the NPE bug when using JNDIRealm/ActiveDirectory in Tomcat 9.0.46 and have a workaround? Context I had to upgrade from 9.0.43 due to a concurrency bug where the socket input stream gets corrupted (and mixing up request bodies) when keep-alive/re-use is enabled. Log was filled with "Error parsing HTTP... | Since you already did the heavy-lifting of finding a patch, the easiest "workaround" is to patch the class affected by the bug. You just need to: Download the patched [CODE] file, Compile it against your Tomcat's jars: [CODE] Put the generated class files in [CODE] . Due to the way the common loader is configured, the ... | 1 | 1 | 659 | 2021-05-17T19:03:50.653 | data_quality | serverfault.com | |
1,048,601 | difference between two registry locations for HKLM\SOFTWARE\Microsoft\Windows\ and HKLM\SOFTWARE\Microsoft\Windows NT\ | What is the difference between the two registry locations [CODE] While my question is asking about the [CODE] i am more interested in the difference between the [CODE] and [CODE] . I have searched online and can't find any solid information to explain why I have duplicate keys in two places and why CIS benchmarks sugge... | I don't have hard evidence or sources for this, but just my personal experience. These are not duplicate keys. Yes, they exists in two places, but have different purposes and are both valid and one shouldn't be preferred over the over. From my experience the [CODE] key was more used in the old days when the OS was actu... | 0 | 1 | 458 | 2021-01-05T04:50:10.003 | data_quality | serverfault.com | |
324,899 | Maintaining consistency with loosely coupled business and data layers | Take the following sequence of events: Business layer requests data [CODE] and [CODE] from data layer. Data layer returns version 1 of [CODE] and [CODE] . Business layer starts performing logic based on data [CODE] and [CODE] . Another (concurrent) operation updates data [CODE] to version 2. Business layer instructs da... | There is a truck sized hole in your use case description: The data z saved in step 5 has now been saved based on inconsistent, or "stale" data. The data x became stale during the business transaction. Say for example, data x holds a flag indicating whether the creation of z data is permitted. This "inconsistent" state ... | 3 | 1 | 551 | 2016-07-15T00:45:42.603 | database_errors | softwareengineering.stackexchange.com | |
504,579 | Looking for Cisco router/switch logs that would be related to an outage | I have a main router with several other switches connected to it. The network went down and when I consoled the main router, it was sluggish. Rebooted it, but once the interfaces where the other switches were connected came up, the router went back to being sluggish. Bounced the switches one by one and everything was b... | Are you logging to a syslog server? If not, the logging buffers on Cisco devices don't survive a reboot by default. If you do have the logs, look at the whole network's worth of messages around the time the problem started. Any interfaces bounce? MAC flapping? Strange errors from any devices? Do you have a monitoring p... | 0 | 2 | 326 | 2013-05-02T18:54:07.547 | infrastructure | serverfault.com | |
1,098,599 | Ubuntu VM SSH session crashes during a large unzip due to kauditd high CPU usage | I am having issues with an Ubuntu 18.08 VM on Azure. The issue seems to occur when I am unzipping a large file with [CODE] . My SSH session crashes out with [CODE] , and I can no longer SSH onto the machine until I restart it on the Azure console. I have checked disk space and it appears to be fine, I think the issue i... | I can't tell why. But I would suggest you use SCREEN or BYOB and unzip in the background. While it unzip the file, juste close your SSH session, get back after a few minutes and VOILA ! | 0 | 0 | 712 | 2022-04-14T12:14:34.957 | pipeline_ops | serverfault.com | |
64,800 | Where do I find the .csv file for the submission after creating it? | I am making a submission of a classificaition problem with CNN on Google Colab. So I have arrived at doing this: [CODE] so in theory I should have finished. The only problem is that I don't know where to find the newly created csv file. Can somebody please help me? Thanks in advance. | When you are done with Colab instince files saves will not persist. You have to configure saving them to google drive. Try something like this; [CODE] so now you can access and save files to google drive directly. | 1 | 2 | 189 | 2019-12-13T21:26:04.883 | data_quality | datascience.stackexchange.com | |
295,512 | Insert query in Orcale database - not showing the row in a table | I am inserting a row in the Oracle database table. The query looks like as below - [CODE] I have executed the above query 3/4 days before. And the result of the query execution was - [CODE] But I do not see the newly added entry in the table. I thought, I need to commit. And now, when I am trying to execute the same qu... | If an insert into the table is hanging using the same primary key value then it suggests there is an open transaction which has inserted this value but not committed yet. You can confirm this by checking for blocked sessions from a sufficiently privileged user: [CODE] Locate your old open SQL*Plus session and run [CODE... | 0 | 1 | 819 | 2021-07-11T11:05:05.703 | database_errors | dba.stackexchange.com | |
1,276 | Severe write performance problem | [Sorry, I tried to stay short but it just was not possible] I'm running Linux 2.6.22.19 with linux-vserver 2.3.0.34 on a Fujitsu Siemens Primergy RX200 S3 for development purpose. Intel(R) Xeon(R) 5140 @ 2.33Ghz with 4GB RAM (where mostly 500MB are still free). The server has two hot-plug 250GB used in a mirroring RAID... | Some good suggestions here from other posters about ruling out the software, and tweaking your RAID performance. It's worth mentioning that if your workload is write-heavy, then going for hardware with a battery-backed write cache is likely to be the right thing to do if you're considering replacing your kit. | 4 | 3 | 2,441 | 2009-04-30T16:58:27.723 | api_errors | serverfault.com | |
1,078,774 | Linux cp specific files from a text list of files to subdirectories from a text list too? | I ask for your help to solve my problem because I am stuck. I explain the situation to you: I want to copy files whose path I have on a txt file in specific subdirectories specified in a second file (I also have a complete csv file including these 2 columns: name of the subdirectories ( [CODE] ), file path ( [CODE] )) ... | The way I've done this in the past is using [CODE] as a go-between -- but I'm sure there are other answers that are more elegant than this. Where we have a list of files that meet a specific criteria IE: all files in /usr smaller than 1M [CODE] That we want to copy to the location [CODE] . You can use tar as a vector t... | 1 | 1 | 199 | 2021-09-27T13:14:53.643 | infrastructure | serverfault.com |
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